1. Field of the Invention
The present invention relates to an inventory management system for managing inventory jobs such as parts storing job, parts collecting jobs and stocktaking jobs.
2. Description of the Prior Art
An electric appliance, for instance, is made up of a great number of parts. To assemble these appliances, various parts are previously stored in a storehouse, collected by an inventory worker according to necessity, and then conveyed to a workship at which the appliances are to be assembled. The conventional method of storing or collecting necessary parts will be described hereinbelow.
In a parts management section, various parts to be stored in a storehouse are usually managed in dependence upon documents referred to as slips. On each slip the kind, the name (code), the number, the weight and the standard of parts are entered. When parts are stored or collected, a shelf on which desired parts are in stock is first searched on the basis of the slip and worker's perception, and then the parts are put in or taken out of a parts container (e.g. box, drawer, etc.) arranged in the searched shelf. Further, after the parts have been stored or collected, the results of the storage or collection are entered in an inventory book.
The above-mentioned parts storing or collecting jobs, there often exists a difference between the number of parts written on the slip and the number actually stored in the container. Therefore, the correct number of parts should be entered on the slip whenever inventory jobs have been completed.
In the above-mentioned conventional parts management method, since the inventory worker checks various parts described on slips (handed over by a person of a management section) and searches the shelves on which the parts are stored, it can takes many hours for a worker having a poor experience to search the shelf and the containers or drawers. Therefore, in case where a single worker cannot collect various parts within a predetermined time, many workers work on the inventory job at the same time. In this case, although each worker engages with the inventory job as instructed a previously determined way of job, it is difficult to determine how the inventory jobs can be accomplished in the shortest possible time, for instance, which worker should take charge of which parts. In addition, when the parts storing job and the parts collecting job are both performed simultaneously, specific parts are subject to interference with each other in both the storing and collecting processes, so that the number of parts in stock vary and thus it is impossible to accurately determine the number of parts stored in a container.
Furthermore, when the worker finds a drawer in which the desired parts are in stock, since all the inventory data should be confirmed by the worker, such as the number of parts previously stored, the number of parts now stored, and the resulting number of parts stored in total, many hours are required for this inventory information confirmation job and more time is consumed for the parts number confirmation job than for the essential parts storing and collecting job.
In summary, the conventional inventory management method has the following drawbacks:
(1) Since the job is performed on the basis of slips, the efficiency is not high and errors inevitably occur.
(2) It takes a long time to find a container position at which target parts are in stock.
(3) Another job is required to confirm the number of parts or to correct the inventory book.